[v1,00/41] RPCSEC GSS krb5 enhancements

Message

Chuck Lever Jan. 13, 2023, 3:21 p.m. UTC

Some light reading for your three-day weekend!

The purpose of this series is to improve/harden the security
provided by the Linux kernel's RPCSEC GSS Kerberos 5 mechanism.
There are lots of clean-ups in this series, but the pertinent
feature is the addition of a clean deprecation path for the DES-
and SHA1-based encryption types in accordance with Internet BCPs.

This series disables DES-based enctypes by default, provides a
mechanism for disabling SHA1-based enctypes, and introduces two
modern enctypes that do not use deprecated crypto algorithms.

Not only does that improve security for Kerberos 5 users, but it
also prepares SunRPC for eventually switching to a shared common
kernel Kerberos 5 implementation, which surely will not implement
any deprecated encryption types (in particular, DES-based ones).

Today, MIT supports both of the newly-introduced enctypes, but
Heimdal does not appear to. Thus distributions can enable and
disable kernel support to match their user space enctype support.

Scott has been kicking the tires -- we've found no regressions with
the current SHA1-based enctypes, and the others are disabled by
default until we have an opportunity for interop testing. The KUnit
tests for the new enctypes pass and this implementation successfully
interoperates with itself using those enctypes. Therefore I believe
it to be ready to merge.

When this series gets merged, the Linux NFS community should select
and announce a date-certain for removal of DES-based enctype code.

---

Chuck Lever (41):
      SUNRPC: Add header ifdefs to linux/sunrpc/gss_krb5.h
      SUNRPC: Remove .blocksize field from struct gss_krb5_enctype
      SUNRPC: Remove .conflen field from struct gss_krb5_enctype
      SUNRPC: Improve Kerberos confounder generation
      SUNRPC: Obscure Kerberos session key
      SUNRPC: Refactor set-up for aux_cipher
      SUNRPC: Obscure Kerberos encryption keys
      SUNRPC: Obscure Kerberos signing keys
      SUNRPC: Obscure Kerberos integrity keys
      SUNRPC: Refactor the GSS-API Per Message calls in the Kerberos mechanism
      SUNRPC: Remove another switch on ctx->enctype
      SUNRPC: Add /proc/net/rpc/gss_krb5_enctypes file
      NFSD: Replace /proc/fs/nfsd/supported_krb5_enctypes with a symlink
      SUNRPC: Replace KRB5_SUPPORTED_ENCTYPES macro
      SUNRPC: Enable rpcsec_gss_krb5.ko to be built without CRYPTO_DES
      SUNRPC: Remove ->encrypt and ->decrypt methods from struct gss_krb5_enctype
      SUNRPC: Rename .encrypt_v2 and .decrypt_v2 methods
      SUNRPC: Hoist KDF into struct gss_krb5_enctype
      SUNRPC: Clean up cipher set up for v1 encryption types
      SUNRPC: Parametrize the key length passed to context_v2_alloc_cipher()
      SUNRPC: Add new subkey length fields
      SUNRPC: Refactor CBC with CTS into helpers
      SUNRPC: Add gk5e definitions for RFC 8009 encryption types
      SUNRPC: Add KDF-HMAC-SHA2
      SUNRPC: Add RFC 8009 encryption and decryption functions
      SUNRPC: Advertise support for RFC 8009 encryption types
      SUNRPC: Support the Camellia enctypes
      SUNRPC: Add KDF_FEEDBACK_CMAC
      SUNRPC: Advertise support for the Camellia encryption types
      SUNRPC: Move remaining internal definitions to gss_krb5_internal.h
      SUNRPC: Add KUnit tests for rpcsec_krb5.ko
      SUNRPC: Export get_gss_krb5_enctype()
      SUNRPC: Add KUnit tests RFC 3961 Key Derivation
      SUNRPC: Add Kunit tests for RFC 3962-defined encryption/decryption
      SUNRPC: Add KDF KUnit tests for the RFC 6803 encryption types
      SUNRPC: Add checksum KUnit tests for the RFC 6803 encryption types
      SUNRPC: Add encryption KUnit tests for the RFC 6803 encryption types
      SUNRPC: Add KDF-HMAC-SHA2 Kunit tests
      SUNRPC: Add RFC 8009 checksum KUnit tests
      SUNRPC: Add RFC 8009 encryption KUnit tests
      SUNRPC: Add encryption self-tests


 fs/nfsd/nfsctl.c                         |   74 +-
 include/linux/sunrpc/gss_krb5.h          |  198 +--
 include/linux/sunrpc/gss_krb5_enctypes.h |   41 -
 net/sunrpc/.kunitconfig                  |   30 +
 net/sunrpc/Kconfig                       |   96 +-
 net/sunrpc/auth_gss/Makefile             |    2 +
 net/sunrpc/auth_gss/auth_gss.c           |   17 +
 net/sunrpc/auth_gss/gss_krb5_crypto.c    |  651 +++++--
 net/sunrpc/auth_gss/gss_krb5_internal.h  |  235 +++
 net/sunrpc/auth_gss/gss_krb5_keys.c      |  416 ++++-
 net/sunrpc/auth_gss/gss_krb5_mech.c      |  732 +++++---
 net/sunrpc/auth_gss/gss_krb5_seal.c      |  122 +-
 net/sunrpc/auth_gss/gss_krb5_seqnum.c    |    2 +
 net/sunrpc/auth_gss/gss_krb5_test.c      | 2040 ++++++++++++++++++++++
 net/sunrpc/auth_gss/gss_krb5_unseal.c    |   63 +-
 net/sunrpc/auth_gss/gss_krb5_wrap.c      |  124 +-
 net/sunrpc/auth_gss/svcauth_gss.c        |   65 +
 17 files changed, 4003 insertions(+), 905 deletions(-)
 delete mode 100644 include/linux/sunrpc/gss_krb5_enctypes.h
 create mode 100644 net/sunrpc/.kunitconfig
 create mode 100644 net/sunrpc/auth_gss/gss_krb5_internal.h
 create mode 100644 net/sunrpc/auth_gss/gss_krb5_test.c

--
Chuck Lever